What are the best Social media platforms for B2B business ?

LinkedIN, Facebook, blogsand it depends on your business, you will never be able to sell row materials through the social media, but you could sell b2b travel or software through the social media its easy too ;)

On B2B is hard to speak about social media platforms because your target is tiny. Social media platforms are used to keep in touch with a big audience and to spread out your messages faster. But on B2B you have a limited number of customers which are companies so it's recommended to use other ways of communication like direct meetings, newsletters, direct marketing or even call them on their's birthday or when you want to congrats them for a success. On B2B it's important to keep in touch every time with your customers and a direct way it's more efficient than a social media platform. 

mostly in B2B social media it is highly recommended to use Linkedin and blogs but you can always create your own way of using social media